Collapsible building form



Feb. 26, 1 929.

1,703,499 E. B. SELWAY COLLAPSIBLE .BUILDING FORM Filed Feb. 2, 1928 2Shets-Sheet 1 J" v I I l N ll 1 gwoentoo E E.B. SeZu/-ay Feb. 26, 1929.1,703,499

E. B. SELWAY GOLLAPSIBLE BUILDING FORM Filed Feb. 2, 1928 2 Sheets-Sheet2 Q wa Patented Feb. 26, 1929.

PATENT LOFFICE.)

EDWARD B, sELwAY, or LEETSDALE, PENNSYLVANIA. f

COLLAPSIBLE BUILDING Form.

Application filed February 2,1928. Serial No. 251,434.

This invention relates to forms designed to be used in connection withthe building of concrete floors, walls and roofs,.and particularly to acollapsible core or form designed to be used in forming hollowconcretewalls,

' the two collapsing rods which have a roofs or floors.

The general object of thG-HIVGDUOH is to provide a form which'maybereadily re,

moved after the concrete has been cast and 10 set.

proved form and of the previously eon- I structed subjacent wall, thestuds being in section;

Figure 2 is a fragmentary elevation of the top ofthe form and studs; 7

Figure 3 is a vertical sectional view of the form; r I

Figure 1 is a transverse section on the line 44 of Figure 1; Figure 5 isa fragmentary section on the line 55 of Figure 3;

Figure 6 is a fragmentary horizontalsee' tion takenfat one end of theform showing the form expanded;

0 Referring to these drawings, it will be,

seen from Figure 1 that the form comprises four steel plates 10, eachhaving. at one endv the flange 11 extending at right angles to thecorresponding plate 10. Two of the plates are used for one side of the[form and two forthe other side and. the plates of each pair overlap, asshown inFigure 1, while the flanges of the plates overlap. Thus theplates may be shifted longitudinally upon 0 each other and laterallyupon each other to thus not only shorten the form but contract it inwidth so that the form, after it has been used as a core, may be readilycollapsed and removed from within the wall. The plates 10 are eachprovided upon its inner face with an outwardly projecting stud bolt 12having A further object is to provide a concrete a nut 13, the heads ofthese stud bolts being inserted in countersunk washers '14, the

washers and the bolts being welded to or otherwise engaged with theplates.

Extending vertically of each form are length equal to or greater thanthe forms, and plvotally engaged with each collapsing rod are the links16, these links 16 in turn.

being pivotally engaged with the bolts 12. Each rod 15 carries theoutwardly projectmg bolt 17 upon which the inner ends of the links 16'are'pivoted, and eaehof these bolts carries the nut 18 and a washer 19surrounding the head of the bolt,the washer and the bolt being welded tothe correspondmg rod 15. Stops 20 act to limit the downward movement ofthe links 16 so that when the links are forced downward to their fullextent they Wlll' be in an approximately horizontal position and thesections of the form will be expanded to the fullest extent Obviously,whenthe rods 15 are drawnupward, the sections will be longitudinallycontracted. r

Preferably binding bar-S 21 are disposed between one pair of plates 10and the oppositepair of plates,..these binding bars extendlng in adiagonal direction. As illustrated, these binding bars engage atone endwith the bolts 12 and are held by the nuts 13, While at. the other endthey. engage 'Withthe bolts 17 of the opposite rod 15. .Thuslt isobviousmthat. when the rods 15 are pulled upward,they will not only actto these bars 21 will act to pull the sections toward each other so asto decrease the width of the form.

F orv the purpose .of urging the form to ts full width and holding itfully expanded against the pressure of material, I mount. upon "the endflange 11 of one of the plates 10 of each pair of plates a plurality oflinks 22, each carrying a roller 23 at one contract the sections towardeach other but.

end, which roller bears against the opposed plate, as shown in Figure 1.The free ends of thelinks 22 are pivotally connected to a rod 24:. Astop 25 is mounted upon the flange 11 of the opposed plate 10 whichlimits the downward movement of the rod 24 to a position where-the links22 are in a'horizontal position. When the rods 24: are depressed, thelinks 22 acting through the rollers 23 will force the. sections of theform apart so as to increasethe width of v elements away from each othercomprising links pivoted to one plate and having rollers engaging withthe opposite plate, and means for shifting said links from or to ahorizontal position.

5. A collapsible form for concrete including oppositely disposed,parallel form elements, means for spacing said elements from each other,means for longitudinally expanding or contracting said elen'ients ortransversely expanding or contracting said elements, and guide barsmounted upon the elements on each face thereof toward the upper end,each guide bar having outwardly deflected portions adapted to ride overthe studding.

6, A collapsible form for concrete including oppositely disposed,parallel form elements, each comprising two overlapping plates, eachplate having an inwardly extending flange, the flange of any one plateoverlapping the flange of an opposite plate on the same side, avertically movable rod associated with each pair of'plates, links'pivotally connecting said rod to the plates of the same pair,diagonally extending loraces pivoted to said rod and extending,

diagonally across to the diagonally opposite .plate and pivotallyengaged therewith, and

EDWARD B. SELWAY.

